This invention relates to an inflatable cuff for use with an instrument for determining the blood pressure of a patient.
Certainly the most used instrument for measuring a patient's systolic and diastolic blood pressure is the sphygmomanometer. That device utilizes a flexible cuff that encircles, typically, a patient's arm and which is thus inflated to increase its pressure to cause changes in the flow of blood within the arterial passages in the patient's arm. By raising that pressure in excess of the patient's systolic pressure and thereafter gradually reducing the cuff pressure, determinations are readily made of the systolic and diastolic pressures.
Other apparatus has, however, been developed, typical of which is disclosed in U.S. Pat. No. 4,406,289, and which makes the measurement of a patient's blood pressure by use of arterial passages in a patient's digit, preferably a finger, rather than the arm. Such apparatus is, under certain conditions, less cumbersome to use and, of course, may be used where access to the patient's arm is difficult or would impede ongoing surgical operations. As noted in U.S. Pat. No. 4,406,289, the finger cuff can also be used with certain specialized apparatus to obtain blood pressure readings on a continuous basis.
It is, therefore, desirable to provide a flexible, inflatable cuff that is designed to encircle a patient's finger, rather than the arm, and which includes, not only an inflatable means to control blood flow in the finger, but a light source and a light detector to carry out the functions described in the aforementioned U.S. Patent.
Certainly it is further desirable that such a cuff be readily manufacturable on a low-cost basis in relatively large quantities of uniform specifications and quality.
Present finger cuffs have been used to detect pulse and other functions that use LED's and light detectors; however, the present inflatable cuff is commercially reproducible in large quanitities with relatively inexpensive manufacturing costs and which are made with sufficient consistency as to have similar characteristics so as to be readily replaceable.